19) In the nitrogen cycle, which of the following plays an important role ?a)Rhizopusb)Mucorc)Nitrobacterd)Spirogyra

20) In nature, the main organisms which take part in the nitrogen cycle area)Parasitic fungib)Legume plantsc)Bacteriad)Saprophytic flowering palnts

21) Rotation of crops is practised becausea)It decreases the nitrogen content of the soilb)It increases the nitrogen content of the soilc)It kills harmful bacteria of the soild)It increases the water content of the soil

22) Even without adding nitrogenous manures a good yield of rice crop can be obtained becausea)Their roots have nitrogen fixing bacteriab)There are nitrogen- fixing algae in rice fieldsc)Rice plants do not require nitrogend)They require minute quantities of nitrogen

23) Which of the following does not help in adding nitrogen to soil?a)Bacterial decay of animal remainsb)Electric lightningc)Addition of lime in soild)Nitrogen fixing bacteria

25) Proteins are made up ofa)Amino acidsb)Nucleic acidsc)Sugarsd)Fatty acids

26) One of the following is a sulphur containing amino acid:a)Valineb)Methioninec)Tryptophand)Phenylalanine

27) Members of the bean family are of particular importance in crop rotation programmes primarily becausea)They add nitrates to the soilb)They manufacture nitrogenous compoundsc)They have nitrogen-fixing bacteria associated in their rootsd)They provide green manure

28) The process by which proteins are synthesized in a cell is called a)Translationb)Transductionc)Translocationd)Transcription

29) A free living anaerobic bacterium capable of nitrogen fixation in soil is a)Azotobacterb)Streptococcusc)Clostridiumd)Rhizobium

42) Which of the following is an example of an insectivorous plant ?a)Brassicab)Cuscutac)Mucord)Nepenthes

43) In some insectivorous plants there is secretion of an acidic enzyme by
which trapped insects are killed and digested. This enzyme isa)Erepsinb)Trypsinc)Strypsind)Amylopsin

44) Heterotrophic nutrition is found ina)Pistiab)Opuntiac)Droserad)Vallisneria

45) By trapping insects the insectivorous plants get
extraa)Sugarb)Proteinc)Waterd)Vitamins

46) In Orobanche which is a root parasite, germination of the seed is dependent ona)Auxins released by the roots of the hostb)Exudates from the roots of the hostc)Exudates released from the parasited)Gibberellins released by the parasitic roots

47) In the nitrogen cycle, nitrite is converted to nitrate
bya)Azotobacterb)Rzhizobiumc)Nitrosomanasd)Nitrobacter

48) The insects captured by the insectivorous plants partially fulfill their
requirement ofa)Enzymesb)Oxygenc)Nitrogend)Water

52) All the following contribute to the available nitrogen compounds in
the soil excepta)Thunderstormb)Animal remainsc)Plant remainsd)Liming

53) Which of the following is an insectivorous plant ?a)Cuscutab)Orobanchec)Droserad)Rafflesia

54) Epiphytes are the plants which are dependent on other plants fora)wateronlyb)water and foodc)food onlyd)shelter (support)

55) The insectivorous plant which has a rosette of prostrate leaves with winged petioles, the lamina consisting of two rounded halves having teeth like
margins devised for catching prey isa)Dionaeab)Droserac)Nepenthesd)Utricularia

56) Nitrogen is present in the atmosphere upto the extent of 78% but plants cannot use it directly becausea)Nitrogen is present in gaseous formb)Gaseous nitrogen is toxic to plantsc)Concentration of nitrogen is too highd)None of the above

60) A tree which is a partial root parasite is a)Loranthusb)Viscumc)Santalumd)Balanophora

61) Which of the following is a total root parasite ?a)Loranthusb)Rafflesiac)Viscumd)Cuscuta

62) Which of the following is a total root parasite ?a)Orobancheb)Viscumc)Cuscutad)Loranthus

63) Which of the following phenomenon is exhibited by Loranthus and Orobanche
?a)Parasitismb)Epiphytismc)Commensalismd)Insectivory

64) Which one of the following statements is correct ?a)Legumes fix nitrogen only through speciallzed bacteria that live in their leavesb)Legumes are incapable of fixing nitrogenc)Legumes fix nitrogen only through the specialized bacteria that live in their rootsd)Legumes fix nitrogen independently of the specialized bacteria that live in their roots

65) Organisms which fix atmospheric nitrogen in the soil come under the
category ofa)Soil fungib)Mossesc)Bacteriad)Green algae

66) Which one of the following species does not have the ability to fix
atmospheric nitrogen ?a)Nostocb)Spirogyrac)Azotobacterd)Anabaena

72) Which of the following is a typical example of ‘feedback Inhibition” ?a) Allosteric inhibition of hexokinase by glucose-6-phosphateb)the reaction between succinic dehydrogenase and succinic acidc) Cyanide and cytochrome reactiond)Sulpha drugs and folic acid synthesizer bacteria

75) The number of ‘floating ribs’ in the human body isa)2 pairsb)5 pairsc)3 pairsd)6 pairs

76) The shortest contraction of any muscle is seen in thea) Jawsb) Eye lidsc) Heartd) Intestine

77) When released from the ovary, a human egg containsa) One Y chromosomeb) Two X chromosomesc) One X chromosomed) X Y chromosomes

78) When yeast ferments glucose the products area) Methanol and CO2b) Ethanol and CO2c) Water and CO2d) Ethanol and water

79) In cheese manufacture micro-organisms are important fora) The souring of milk onlyb) The ripening onlyc) The development of resistance to spoilage onlyd) Both the souring and the ripening processes

80) The production of nitrates from ammonia through Nitrosomonas is calleda) Nitrificationb) Ammonificationc) Nitrogen fixationd) Denitrification

81) Plants are similar to animals becausea) They respire during the nightb) They respire during the day and nightc) They respire when it is requiredd) They respire during the day only

82) In Chlamydomonas chlorophyll is found in thea) Pyrenoidsb) Granac) Stigmad) Thylakoids

83) Agaricus cannot manufacture its own food becausea) They do not have leavesb) They lack chlorophyllc) They do not need foodd) They have no roots

84) Minerals are absorbed by a plant from the soil by the process a) Independent of water absorptionb) Dependent on water absorptionc)Dependent on the strength of solutionsd) Dependent on osmosis

c)the concentration of the soil solution is higher than that of the celld) It has no hygroscopic water

92) The direction and rate of water movement from cell to cell is based ona) W.P.b) T.P.c) D.P.Dd) Incipient plasmolysis

93) During transport of sugar or amino acids through the cell membranea)Na+ ions move against the direction of
concentration gradient

b)Na+ ions move in both directions irrespective
of its concentration gradient

c)No net Na+ ions movement

d)Na+ ions move in the direction of the
concentration gradient

94) “Osmosis is the flow of a solution from higher concentration to a solution of lower concentration through a semi-permeable membrane.” What is incorrect in this statement?a)The exact concentration of the solution is not givenb)The character of the semi-permeable membrane is not givenc)The flow of solution is not possible through a semi permeable membraned) All are incorrect

95) Prolonged water-logging causes death of plants becausea) Root respiration stopsb) Cell sap in the plants becomes very dilutec) Nutrients leach down due to excess waterd) Soil nutrients become very dilute

96) Stomata in Angiosperms open and close due toa) Their genetic constitutionb)the effect of hormonesc)Changes of turgor pressure in the guard cellsd) Pressure of gases inside the leaves

97) The apparatus generally used for studying the rate of transpiration stream is thea) Potometerb) Evaporimeterc) Atmometerd) Perimeter

98) Spraying of phenyl mercuric acetate (PMA)a) Increases the rate of guttationb) Increases the rate of transpirationc)Decreases the rate of transpirationd) Increases the rate of water absorption

100) An effective adaptation for better gas exchange in plants is thea)Large number of hairs on the lower epidermisb)Presence of stomata on the lower surface of the leafc) Multiple epidermisd) Waxy cuticle